We've done a cool $50 million of R & D on the Apple Human Interface.
We discovered, among other things, two pertinent facts:

Test subjects consistently report that keyboarding is faster than mousing.

The stopwatch consistently proves mousing is faster than keyboarding.

This has caused many arguments and discussions (eg: by Jeff Atwood and at skeptics.SE, but all of these are based on subjective assumptions.

So, I'm looking for some other, newer studies that could either verify or refute those findings from the 80's. Are there any recent studies on the "Keyboard vs Mouse"-issue?

I'm concerned about two aspects:

The time aspect. Performance vs preference.

The workload aspect. What's the learning curve like? How many shortcuts does the novice user use, and how many shortcuts are the experienced user able to handle?

Update:

I don't doubt that keyboard shortcuts are faster is many situations, but I would like to see some more research on the issue. Conducting one myself isn't an option (and it would be unnecessary if it's already done). Subjective opinions and referral to "the obvious" won't give me the answers I'm searching either.

KLM/GOMS/MHP are all good models that could function as a theoretical basis to explain what's happening. Any reference to any such work on this area would be good too...

So why am I asking about this?
Well, as a UX professional, I would like to base my stack of knowledge on research, not assumptions. IMHO, the fundamentals of UX are based on "find out, don't assume".

It can be difficult to convince people about the UX-work. Having proper research is one of the most important tools we have. (Letting them observe users use their software is the most important one).

But it is so obvious!...
No it isn't. When users are confronted with multiple design options, the correlation between preference and performance is very low. Only 25% would prefer the solution with the best performance.

We also know that heavy mental workload makes you think that you're effective, even if you're not (just like the Apple research concluded). So the feeling "this is the fastest solution" doesn't actually make it the fastest solution.

Why is it important to know this? Just provide both, and let the users choose!
Well, if I'm going to train a user group, I would want to base my advises on something. Right now, the only research I can base my advice on says "Minimize the use of shortcuts. You'll just fool yourself and believe you're faster than you actually are."

Performance differences. (Something can be worked out from the KLM/GOMS theories.)

What is the performance improvement for the shortcuts you remember immediately.

What is the performance loss (if any) in the situations where you have to "think twice" to remember a shortcut.

What is the "recovery cost" in the situations where you use the wrong shortcut (or didn't remember it after thinking twice).

Will the mental workload of "remembering" a shortcut affect the main work task? Say you're doing accounting and need to handle 5-7 "chunks" of information already.

Are there any thresholds you can use to say: "Just use N number of keyboard shortcuts and stick to the mouse+toolbar for the other commands."

What would the capability/advice be for each of these cells:

I know these questions are very specific, and that's why I kept the question general in the first place.

Remember: I'm just asking for references to any research, I'm not asking for a winner or a conclusion, nor am I asking for specific answers to the issues I've raised in the "update" section above. This question is answerable...

This is going to depend on the task you are comparing. If you've watched an expert Vim user, there is no doubt that the keyboard is faster than the mouse for that. For graphics programs, maybe not.
–
JohnGB♦Dec 17 '12 at 13:04

1

I Agree with John. This question is so context/task/personal preference sensitive that it looks impossible to generally declare one being more efficient than the other.
–
AndroidHustleDec 17 '12 at 13:19

2

The mouse is always slower when I do most of the work using the keyboard. The keyboard is always slower when I do most of the work using the mouse. In other words: slowness is not function of mouse or keyboard use, but of having to switch from one to the other.
–
Marjan VenemaDec 17 '12 at 13:23

1

@JørnE.Angeltveit it would only apply to the narrow situation that is being studied. Imagine having to use a mouse for text entry - painful. Imagine drawing with a keyboard - equally painful. Most applications lie somewhere between those two extremes.
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JohnGB♦Dec 17 '12 at 13:37

Previous research comparing methods of issuing commands
found that selecting a toolbar item is faster than selecting
an item from two menus with either a mouse or keyboard
shortcut. Over the course of 90 trials, however, the keyboard
method showed the most improvement, nearing the toolbar
response time. The study presented in this paper compared
the response time of the keyboard method across 240 trials
when items were drawn from a single versus two menus. Throughout the trials,** the 1-menu condition produced selection
times that were on average 600 ms to 800 ms faster than
the 2-menu condition** suggesting users in the 2-menu condition
were not able to bypass the menu decision by chunking
the 3-key sequence into one cognitive unit. [...]
Previous studies have shown that practiced users can select a command
faster using a simple key sequence than by using the mouse to select
the menu from a toolbar or menu [6, 7, 9]. In these studies, the simple keyboard command
typically includes a control-key followed by a single key
press for choosing the command. In contrast, a more recent
study [10] suggests that more complex key sequences do not have such a clear advantage over toolbar selection. [...] Perhaps with more practice,
users would eventually chunk the whole key sequence
as one unit for selecting a command.
[...]
Throughout the trials, the 1-menu condition produced selection
times that were on average 600 ms to 800 ms faster than
the 2-menu condition. Since both conditions required participants
to type the same key presses, this difference in time
indicates the mental cost of category selection.

[...] It would seem natural for users to migrate from
the use of easy-to-learn menu and icon methods to the more efficient method of keyboard
shortcuts as they gain experience. To investigate the extent to which this transition
takes place, 251 experienced users of Microsoft Word were given a questionnaire
assessing their choice of methods for the most frequently occurring commands. Contrary
to our expectations, most experienced users rarely used the efficient keyboard
shortcuts, favoring the use of icon toolbars instead. A second study was done to verify
that keyboard shortcuts are, indeed, the most efficient method. Six participants performed
common commands using menu selection, icon toolbars, and keyboard shortcuts.
The keyboard shortcuts were, as expected, the most efficient. We conclude that
even experienced users are inefficient in their use of graphical interfaces. One possible
way to improve user efficiency is for training programs to provide a roadmap for users
to make the transition from using pull-down menus and clicking icon toolbars to issuing
keyboard shortcuts.

Overall, the Toolbar-Mouse method was the fastest, while the Menu-Keyboard condition showed the most
improvement. A GOMS-based model is presented that accounts for differences among methods. This work
confirms the use of toolbars for common commands, but also suggests that for heavily-used interfaces, keyboard
shortcuts can be as efficient as toolbars and have the advantage of providing fast access to all commands.

I don't see the need for any new studies in this area. The issue is that people usually take the results out of context. You can't comparing using a mouse to learning a keyboard command and then using it. Apples and oranges. Let me summarise what we know.

If you don't know the keyboard command, it is usually faster to use the mouse as it has a lower learning curve.

If you do know the command, the keyboard is much faster than the mouse. But then you have to have taken the time to learn it.

In my mind the issue is not that pressing for most applications as you should strive to allow both methods so that people can choose the way that suits them most. If they are going to invest time into becoming more efficient in a program they will typically use the keyboard more, but if it's something they will rarely use, then they will opt for a mouse more often than not.

It's the research behind "If you do know the command the keyboard is much faster than the mouse" I'm looking for. I'm not sure if this statement is true (or rather: I would prefer to be able to back that statement up with some research).
–
Jørn E. AngeltveitDec 17 '12 at 13:39

2

Based on the KLM and GOMS model, John's statement (If you don't know the keyboard command, it is usually faster to use the mouse) is absolutely correct. Mentally preparing takes ~ 1.35 seconds, moving hands to keyboard from mouse takes ~ .4 seconds, pointing with a mouse (excluding click) takes ~ 1.1 seconds, etc. You can review "The Psychology of Human Computer Interaction" by Stuart Card, Thomas Moran and Allen Newell or simply search for any research related to GOMS for more information.
–
superduperflyDec 17 '12 at 13:56

I cannot quote a body of research to convince you of my POV, but perhaps you can run your own test and reach your own conclusion. Take a graphics designer in PS who deserves the rank of 'legendary' and record the time it takes and the number of keyboard shortcuts they use in a session. Then ask them to do the same thing using only the mouse. You shouldn't need a stopwatch to reach a conclusion. I generally agree with the other comments here that it all depends on the actions taken and knowledge of the software.
–
ShashDec 17 '12 at 20:09

@JørnE.Angeltveit I would see a need for new studies if they were answering a question which would be applicable and for which we did not have existing results. It's like having a study on whether a car is faster than a person. It depends on the environment you are testing in.
–
JohnGB♦Dec 18 '12 at 19:11

@JørnE.Angeltveit you missed the point. On a nice tarred road car wins. On a narrow path up a mountain the person wins. The point is that each application will be different, and so the result will have to be only loosely applicable. That is already satisfied by existing studies.
–
JohnGB♦Dec 19 '12 at 1:22

As it is written it depends of the user experience and the software goal. An expert uses more keyboard more than beginners.
A texte data appplication (exemple CRM) is more used with keyboard and a bitmap drawing software is more used with mouse and a vectorial drawing software is more used with both to cut, paste, copy, paste, group, ungroup for exemple with keyboard, move objects slowly with arrow keyboard and select or rapidly move with mouse.

Similar to how we can explore an application with mouse, we can actually explore an application using keyboard too. When I want to check out the menu I just press Alt on Windows and navigate with cursor keys. Or I hold Alt key and see what gets underlined and press that letter.

When you learn that universal language once, learning application specific functionality for keyboard may not be too different than the mouse. You actually perform the same ritual with mouse too only you're not aware of it. When you use your paint program, if the icon is unfamiliar, you hover on it to learn what it does, and when you do that in some cases you are presented with a shortcut key in parantheses too.

Despite their commonality there are two very important differences between the two:

Not that any of the above True Facts will stop the religious wars. And, in fact, I find myself on the opposite side in at least one instance, namely editing. By using Command X, C, and V, the user can select with one hand and act with the other. Two-handed input. Two-handed input can result in solid productivity gains (Buxton 1986).

It ultimately depends on the scenario and function for comparison, instead of judging one against the other you need to measure the two in conjuction. 2¢